Access key. If not missing, it must be a
single character string that is partially matched against
the available algorithms in the registry. In this case,
if all=FALSE
(default), then the algorithm is
returned as an NMFStrategy
object that can be
directly passed to nmf
. An error is thrown
if no matching algorithm is found.
If missing or NULL
, then access keys of algorithms
-- that match the criteria version
, are returned.
This argument is assumed to be regular expression if
all=TRUE
or version
is not NULL
.